Figures 2(a) and 2(b) show the results for a batch distillation column operating at constant reflux ratio of 2.0 with ten theoretical stages. In Figure 2(a) it is observed that at the bottom of the column, the composition of benzene decreased with time while the composition of the heavy components increased.arolo and Guarice [ 8 ] extended their continuous short-cut method to batch distillation columns and used an infinite stage column. Seader and Henley [ 9, 10 ] applied Sundaram and Evans [ 3 ] method and showed how the FUG equations were used to solve a simulation problem with constant reflux.
Executive Summary on Persistence and Retention Topics. â¢ Retention rates commonly measure the percentage of freshmen that re-enroll the next academic year as sophomores. The primary reason that retention rates, along with graduation rates, are important is that retention rates are. perceived as indicators of academic quality and student success. â¢ In addition to retention, persistence, a studentâs continuation behavior leading to a desired goal, helps describe.
[edit] Introduction. Retention is a percentage (often 5%) of the amount certified as due to the contractor on an interim certificate, that is deducted from the amount due and retained by the client.The purpose of retention is to ensure that the contractor properly completes the activities required of them under the contract.Retention can also be applied to nominated sub-contractors, and the main contractor may also apply retention to domestic sub-contractors. possible alternative to retention is a retention bond, where the client agrees to pay the amounts which would otherwise have been held as retention, but instead a bond is provided to secure the amount that would have been retained.